毛乌素沙地三种植被下苔藓结皮的土壤理化效应

分析了沙蒿、沙柳、樟子松三种植被下有苔藓结皮、无苔藓结皮（对照）样地0—2，2—5，5—10 cm剖面土壤的理化指标，探讨毛乌素沙地苔藓结皮对土壤理化性状的影响及其与植被类型的关系。结果表明:（1）三种植被下苔藓结皮均能够明显提高土壤稳定性，增加细砂粒（0.02～0.2 mm）含量、降低粗砂粒（0.2～2 mm）含量。（2）沙柳及沙蒿植被下苔藓结皮均能够显著提高各层土壤的有机质、全氮、速效钾、全磷含量（P>0.05），降低全钾、速效磷含量；樟子松下苔藓结皮0—2 cm剖面的理化效应同沙柳、沙蒿类似，但2—5，5—10 cm剖面内，有机质含量显著降低（P>0.05），全氮、全钾、全磷、速效磷含量则无显著变化（P<0.05）。（3）荒漠生态恢复过程中，苔藓结皮对土壤理化性状的改善作用主要集中在表层土壤，改善程度同植被类型的关系密切。

Effects of Moss Dominated Crusts on Soil Physicochemical Properties Under Three Types of Vegetation in Mu Us Sandland

The soil physicochemical properties in the sites where were covered and uncovered (control) by moss crusts under Artemisia ordosica, Salix cheilophila Schneid and Pinus sylvestris Linn. var. mongolica Litv. at 0—2, 2—5, 5—10 cm depths were analyzed respectively. The effects of moss crusts on the soil physicochemical properties and its relationship between the type of vegetation were discussed. The results are as follows: (1) the moss crusts under three types of vegetation are able to significantly increase the soil stabilization，increase the proportion of fine sand (0.02～0.2 mm) and decrease the proportion (0.02～0.2 mm) of coarse sand; (2) the moss crusts under Artemisia ordosica and Salix cheilophila Schneid. can significantly increase the contents of soil organic matter, total N, available K and total P. Meanwhile, it’s able to decrease the contents of total K and available P in 0—2, 2—5, 5—10 cm depths, respectively. The effects of moss crusts under Pinus sylvestris Linn. var. mongolica Litv. at 0—2 cm depths were similar with those of Artemisia ordosica and Salix cheilophila Schneid. The difference is the moss crusts under Pinus sylvestris Linn. var. mongolica Litv. can significantly decrease the content of soil organic matter and have no significant effects on the contents of total N, total K, total P and available P at 2—5 cm and 5—10 cm depths; (3) in the process of ecology restoration in desert, the improvement of moss crusts on soil hysicochemical properties mainly focuses on the shallow layer and the improvement degree has close relations with the type of vegetation.